1. Field of the Invention
The present invention relates to a bottle washing nozzle in order to wash the interior of a bottle with a washing liquid, prior to filling contents into the bottle, in a contents filling line, or the like.
2. Description of the Related Art
In recent years, various sterilization and filling methods have been used as bottle filling methods, which prevent deterioration of the flavor of the contents due to heating, while maintaining a state of high quality. During sterilization and filling, the interior of the bottle is sterilized with a sterilization liquid, whereupon aseptic water is jetted inside the bottle, thereby flushing out and removing the sterilization liquid, but in the case of synthetic resin bottles such as a PET (polyethylene terephthalate) bottle, there are ribs, indentations and projections in a body wall, and although it is possible to wash completely points which are difficult to clean, such as ribs, indentations and projections, or corner sections, simply by means of introducing a washing nozzle through a bottle opening and jetting a washing liquid inside the bottle, provided that the liquid is jetted for a long period of time, it is difficult to sterilize the bottle by means of sterilization liquid and to completely flush out the sterilization liquid, subsequently, in a short period of time in a high-speed line. In particular, this is even more difficult in cases when the bottle has a non-circular, quadrilateral cross-section.
Conventionally, as a device for uniformly washing the inner surfaces of the bottle, it is common to combine use of jetting the washing liquid from the center of the nozzle, and jetting from the periphery thereof (see, for example, the Japanese Patent Publication No. S63-82989, and the Utility Model Publication No. H3-75853). However, in this case, since the bottle is cleaned by means of washing liquid jetted directly onto the inner surfaces of the bottle from both nozzles, there is a drawback in that a large quantity of washing liquid is required and washing efficiency is poor. In order to resolve this problem, as a method for washing the interior of a bottle more efficiently, the present inventors have devised a two-stage nozzle having a first jet orifice which opens at the front end section, and a second jet orifice which opens at a position below the front end section, and they have proposed a method for washing using this two-stage nozzle (see, for example, the Japanese Patent Publication No. 2003-181404).
The washing method according to the Japanese Patent Publication No. 2003-181404 is performed efficiently by reducing the time required for sterilization and washing of the inner surfaces of the container, without having to produce a relative swaying motion between the container and the bottle washing nozzle, and it aims to simplify the equipment required for sterilization and washing. However, the proposed washing nozzle is suitable for washing bottles having opening diameters within a certain specific range, but it does not allow efficient washing by means of the same washing nozzle when washing bottles having widely varying opening diameters due to model switching. Therefore, washing nozzles of different sizes must be used in accordance with the diameter of the opening in the bottle. For example, there is a problem in that if a bottle having a 38 dia. opening is washed with a washing nozzle designed for a bottle having a 28 dia. opening, then the dispersive effect of the washing liquid inside the container is lost, and all of the internal surfaces of a bottle having ribs or other indentations and projections, or a bottle of square cross-section having corner sections, or the like, are not wetted by the washing liquid, and hence washing non-uniformities arise.